滴灌量对冬小麦耗水特性和干物质积累分配的影响

为给滴灌冬小麦高产栽培的水分管理提供理论依据,在播前足墒和越冬前灌水750 m33·hm-2的条件下分析了起身后不同滴灌量(2550、3150和3750 m3·hm-2,分别用W1、W2、W3表示)对冬小麦耗水及干物质积累、分配的影响.结果表明,随滴灌量的减少,冬小麦孕穗期至花后20 d的0～100 cm土层含水量明显降低,但土壤含水量沿毛管的横向差异增大,总耗水量减少,土壤贮水的消耗量明显增加;群体的叶面积指数和干物质积累量降低,尤其是远离毛管处下降更明显;开花前营养器官贮藏同化物向籽粒的转运量、运转率及对籽粒的贡献率增加,开花后干物质同化量和对籽粒的贡献率显著降低;籽粒产量降低,灌溉水利用效率呈增加趋势.3个处理中,W2的水分利用效率最高,产量与W3差异不显著.在本试验条件下,起身后滴灌冬小麦的适宜灌溉定额为3150～3750 m3·hm2.

Effect of Different Amount of Drip Irrigation on Water Consumption Characteristics and Dry Matter Accumulation and Distribution in Winter wheat

A field experiment were conducted using Xindong 33 cultivar, and three drip irrigation treatments of 2 550 m³·hm^-2(W₁), 3 150 m³·hm^-2(W₂) and 3 750 m³·hm^-2(W₃) after erecting stage to study the effects of different drip irrigation on water consumption characteristics and dry matter accumulation and distribution in winter wheat under full water supply before seeding and the irrigation of 750 m³·hm^-2 before over winter stage.The results showed that along with the reduction of drip irrigation quantities, the water content in the 0~100 cm soil from booting to 20 days after flowering (20DAF) reduced greatly; but with the reduction of drip irrigation quantities, significant difference was observed among the same treatments on transverse relative soil moisture, and the total water consumption decreased, however, soil stored water consumption increased. With drip irrigation quantities decreased, reduction on leaf area index (LAI) and dry matter accumulation of the population were observed,obviously, especially where more far away from the soil capillary, but the dry matter translocation of vegetative organ before anthesis, its ratio and contribution to grains increased, while dry matter accumulation after anthesis and its contribution to grains were the opposite. Grain yield of W₁ was lower than that of W₂ and W₃, the irrigation water use efficiency (IWUE) of W₁ were significantly higher than those of W₂ and W₃, and the water use efficiency (WUE) of W₂ was the highest, with 1.5 kg·m^-3, and grain yield of 9 045.4 kg·hm^-2. Therefore, 3 150~3 750 m³·hm^-2 could be the suitable irrigation quota of drip irrigation for winter wheat.